Comparison of nasal and bronchial mucociliary clearance in young non-smokers.

1. Nasal and bronchial mucociliary clearance have been studied in ten non-smokers (aged 19-23 years). Nasal mucociliary transport was evaluated by measuring the transport rate of a single radioactive (99mTc) particle deposited on the nasal mucosa. Bronchial clearance was measured after inhalation of insoluble radioactive anionic particles (diameter 7.4 +/- 1.5 micrometer). The initial deposition of the aerosol and subsequent clearance over 1 h was monitored with a gamma-camera. 2. The initial particle deposition was concentrated centrally and was similar in all subjects. The percentage of the total deposition located in the central zone was 78.2 +/- 5.8. The range for nasal transport rate (0-12.6 mm/min) and bronchial mucociliary clearance (18.6-77.0%) was large. 3. An inverse relationship (rS = -0.63, P less than 0.05) was observed between nasal transport rate and bronchial clearance, suggesting that, in young non-smokers, the lower the rate of the nasal mucociliary transport the faster the bronchial mucociliary clearance.